Rather then wasting blocks and bricks by converting them to bits (one block only makes 2 bits, a rip off) make a deal with a local smith. They often need blocks to make acrylia plate armor. I have a smith friend and what we do is trade blocks and bricks for peices. He gives me 6 peices for a block, 3 for a large brick. This way he gets the blocks he needs and I get the bits I need. We usually farm at different times and in different area's so we're not competeing for mobs either. A very effecient system.
Good luck.
Novaa Starshine 58th Druid of Karana